The State Department was hit in two separate locations last week by a thief who got away with dozens of cellphones and electronic equipment.

The department acknowledged that one individual is suspected of slipping into two of its buildings — one in Washington and one in Arlington. A suspect was arrested after he allegedly tried to sell the equipment at a restaurant in Virginia, and almost all the stolen devices were retrieved.

The suspect was identified by Arlington police as Joel Enriquez-Bueno, 42, with no known fixed address. He was charged with grand larceny, grand larceny with intent to sell, breaking and entering, and giving a false identity to police. It was not clear whether he had retained an attorney. He was being held without bond in the Arlington County Detention Facility.

It is unclear why someone apparently targeted two different State Department facilities across the river from each other on the same day, suggesting they were not chosen at random. It also is unclear whether it is just a coincidence that the thefts happened during the government shutdown that has furloughed 4 in 10 State Department employees, or whether the thief failed to realize that Diplomatic Security, which is responsible for protecting property as well as lives, is fully staffed despite the shutdown.

A State Department official, who spoke on the condition of anonymity to discuss the mysterious incident, said, “We continue to meet security staffing requirements” but declined to discuss the details. The official said a thief had entered two State Department annexes on Jan. 3. The official did not say whether the person succeeded in getting past security to reach interior offices at the Washington building.

More is known about the incident in Rosslyn. According to the Arlington County Police Department, officers were dispatched around 11 a.m. to a building in the 1800 block of North Lynn Street. A high-rise building on that block houses the State Department’s Office of Personnel Security and Suitability, where security clearances for all State Department employees are checked and processed.

Police said a man had “piggybacked” into the secure building at 9:35 a.m., slipping in behind someone else, made his way to an upper-floor suite and allegedly stole 53 electronic devices, including 44 cellphones that were a combination of private and government-owned phones. It is unclear why so many phones were in one place, but government employees often check their phones before entering secure areas. Police declined to specify what other electronic devices were taken.

Police determined the thief went to a restaurant less than half a mile away on Fort Myer Drive and attempted to sell them. While canvassing the area, they located a man they said matched the thief’s description and took him into custody. Police recovered all the stolen equipment except for one set of headphones, said police spokeswoman Ashley Savage. The State Department said it does not believe the purloined phones contained any classified material.